Merge pull request #12372 from vjpai/armalarmadingdong

Core API change: Decouple alarm construction from setting to avoid races in MT code

18 files changed, 172 insertions, 78 deletions

diff --git a/Makefile b/Makefile
index 66c99f5dcf..f04d5838e2 100644
--- a/Makefile
+++ b/Makefile
@@ -410,7 +410,7 @@ E = @echo
 Q = @
 endif
 
-CORE_VERSION = 4.0.0-dev
+CORE_VERSION = 5.0.0-dev
 CPP_VERSION = 1.7.0-dev
 CSHARP_VERSION = 1.7.0-dev
 
@@ -460,7 +460,7 @@ SHARED_EXT_CORE = dll
 SHARED_EXT_CPP = dll
 SHARED_EXT_CSHARP = dll
 SHARED_PREFIX =
-SHARED_VERSION_CORE = -4
+SHARED_VERSION_CORE = -5
 SHARED_VERSION_CPP = -1
 SHARED_VERSION_CSHARP = -1
 else ifeq ($(SYSTEM),Darwin)
@@ -2628,7 +2628,7 @@ install-shared_c: shared_c strip-shared_c install-pkg-config_c
 ifeq ($(SYSTEM),MINGW32)
 	$(Q) $(INSTALL) $(LIBDIR)/$(CONFIG)/libgpr$(SHARED_VERSION_CORE)-dll.a $(prefix)/lib/libgpr.a
 else ifneq ($(SYSTEM),Darwin)
-	$(Q) ln -sf $(SHARED_PREFIX)gpr$(SHARED_VERSION_CORE).$(SHARED_EXT_CORE) $(prefix)/lib/libgpr.so.4
+	$(Q) ln -sf $(SHARED_PREFIX)gpr$(SHARED_VERSION_CORE).$(SHARED_EXT_CORE) $(prefix)/lib/libgpr.so.5
 	$(Q) ln -sf $(SHARED_PREFIX)gpr$(SHARED_VERSION_CORE).$(SHARED_EXT_CORE) $(prefix)/lib/libgpr.so
 endif
 	$(E) "[INSTALL] Installing $(SHARED_PREFIX)grpc$(SHARED_VERSION_CORE).$(SHARED_EXT_CORE)"
@@ -2637,7 +2637,7 @@ endif
 ifeq ($(SYSTEM),MINGW32)
 	$(Q) $(INSTALL) $(LIBDIR)/$(CONFIG)/libgrpc$(SHARED_VERSION_CORE)-dll.a $(prefix)/lib/libgrpc.a
 else ifneq ($(SYSTEM),Darwin)
-	$(Q) ln -sf $(SHARED_PREFIX)grpc$(SHARED_VERSION_CORE).$(SHARED_EXT_CORE) $(prefix)/lib/libgrpc.so.4
+	$(Q) ln -sf $(SHARED_PREFIX)grpc$(SHARED_VERSION_CORE).$(SHARED_EXT_CORE) $(prefix)/lib/libgrpc.so.5
 	$(Q) ln -sf $(SHARED_PREFIX)grpc$(SHARED_VERSION_CORE).$(SHARED_EXT_CORE) $(prefix)/lib/libgrpc.so
 endif
 	$(E) "[INSTALL] Installing $(SHARED_PREFIX)grpc_cronet$(SHARED_VERSION_CORE).$(SHARED_EXT_CORE)"
@@ -2646,7 +2646,7 @@ endif
 ifeq ($(SYSTEM),MINGW32)
 	$(Q) $(INSTALL) $(LIBDIR)/$(CONFIG)/libgrpc_cronet$(SHARED_VERSION_CORE)-dll.a $(prefix)/lib/libgrpc_cronet.a
 else ifneq ($(SYSTEM),Darwin)
-	$(Q) ln -sf $(SHARED_PREFIX)grpc_cronet$(SHARED_VERSION_CORE).$(SHARED_EXT_CORE) $(prefix)/lib/libgrpc_cronet.so.4
+	$(Q) ln -sf $(SHARED_PREFIX)grpc_cronet$(SHARED_VERSION_CORE).$(SHARED_EXT_CORE) $(prefix)/lib/libgrpc_cronet.so.5
 	$(Q) ln -sf $(SHARED_PREFIX)grpc_cronet$(SHARED_VERSION_CORE).$(SHARED_EXT_CORE) $(prefix)/lib/libgrpc_cronet.so
 endif
 	$(E) "[INSTALL] Installing $(SHARED_PREFIX)grpc_unsecure$(SHARED_VERSION_CORE).$(SHARED_EXT_CORE)"
@@ -2655,7 +2655,7 @@ endif
 ifeq ($(SYSTEM),MINGW32)
 	$(Q) $(INSTALL) $(LIBDIR)/$(CONFIG)/libgrpc_unsecure$(SHARED_VERSION_CORE)-dll.a $(prefix)/lib/libgrpc_unsecure.a
 else ifneq ($(SYSTEM),Darwin)
-	$(Q) ln -sf $(SHARED_PREFIX)grpc_unsecure$(SHARED_VERSION_CORE).$(SHARED_EXT_CORE) $(prefix)/lib/libgrpc_unsecure.so.4
+	$(Q) ln -sf $(SHARED_PREFIX)grpc_unsecure$(SHARED_VERSION_CORE).$(SHARED_EXT_CORE) $(prefix)/lib/libgrpc_unsecure.so.5
 	$(Q) ln -sf $(SHARED_PREFIX)grpc_unsecure$(SHARED_VERSION_CORE).$(SHARED_EXT_CORE) $(prefix)/lib/libgrpc_unsecure.so
 endif
 ifneq ($(SYSTEM),MINGW32)
@@ -2672,7 +2672,7 @@ install-shared_cxx: shared_cxx strip-shared_cxx install-shared_c install-pkg-con
 ifeq ($(SYSTEM),MINGW32)
 	$(Q) $(INSTALL) $(LIBDIR)/$(CONFIG)/libgrpc++$(SHARED_VERSION_CPP)-dll.a $(prefix)/lib/libgrpc++.a
 else ifneq ($(SYSTEM),Darwin)
-	$(Q) ln -sf $(SHARED_PREFIX)grpc++$(SHARED_VERSION_CPP).$(SHARED_EXT_CPP) $(prefix)/lib/libgrpc++.so.4
+	$(Q) ln -sf $(SHARED_PREFIX)grpc++$(SHARED_VERSION_CPP).$(SHARED_EXT_CPP) $(prefix)/lib/libgrpc++.so.5
 	$(Q) ln -sf $(SHARED_PREFIX)grpc++$(SHARED_VERSION_CPP).$(SHARED_EXT_CPP) $(prefix)/lib/libgrpc++.so
 endif
 	$(E) "[INSTALL] Installing $(SHARED_PREFIX)grpc++_cronet$(SHARED_VERSION_CPP).$(SHARED_EXT_CPP)"
@@ -2681,7 +2681,7 @@ endif
 ifeq ($(SYSTEM),MINGW32)
 	$(Q) $(INSTALL) $(LIBDIR)/$(CONFIG)/libgrpc++_cronet$(SHARED_VERSION_CPP)-dll.a $(prefix)/lib/libgrpc++_cronet.a
 else ifneq ($(SYSTEM),Darwin)
-	$(Q) ln -sf $(SHARED_PREFIX)grpc++_cronet$(SHARED_VERSION_CPP).$(SHARED_EXT_CPP) $(prefix)/lib/libgrpc++_cronet.so.4
+	$(Q) ln -sf $(SHARED_PREFIX)grpc++_cronet$(SHARED_VERSION_CPP).$(SHARED_EXT_CPP) $(prefix)/lib/libgrpc++_cronet.so.5
 	$(Q) ln -sf $(SHARED_PREFIX)grpc++_cronet$(SHARED_VERSION_CPP).$(SHARED_EXT_CPP) $(prefix)/lib/libgrpc++_cronet.so
 endif
 	$(E) "[INSTALL] Installing $(SHARED_PREFIX)grpc++_error_details$(SHARED_VERSION_CPP).$(SHARED_EXT_CPP)"
@@ -2690,7 +2690,7 @@ endif
 ifeq ($(SYSTEM),MINGW32)
 	$(Q) $(INSTALL) $(LIBDIR)/$(CONFIG)/libgrpc++_error_details$(SHARED_VERSION_CPP)-dll.a $(prefix)/lib/libgrpc++_error_details.a
 else ifneq ($(SYSTEM),Darwin)
-	$(Q) ln -sf $(SHARED_PREFIX)grpc++_error_details$(SHARED_VERSION_CPP).$(SHARED_EXT_CPP) $(prefix)/lib/libgrpc++_error_details.so.4
+	$(Q) ln -sf $(SHARED_PREFIX)grpc++_error_details$(SHARED_VERSION_CPP).$(SHARED_EXT_CPP) $(prefix)/lib/libgrpc++_error_details.so.5
 	$(Q) ln -sf $(SHARED_PREFIX)grpc++_error_details$(SHARED_VERSION_CPP).$(SHARED_EXT_CPP) $(prefix)/lib/libgrpc++_error_details.so
 endif
 	$(E) "[INSTALL] Installing $(SHARED_PREFIX)grpc++_reflection$(SHARED_VERSION_CPP).$(SHARED_EXT_CPP)"
@@ -2699,7 +2699,7 @@ endif
 ifeq ($(SYSTEM),MINGW32)
 	$(Q) $(INSTALL) $(LIBDIR)/$(CONFIG)/libgrpc++_reflection$(SHARED_VERSION_CPP)-dll.a $(prefix)/lib/libgrpc++_reflection.a
 else ifneq ($(SYSTEM),Darwin)
-	$(Q) ln -sf $(SHARED_PREFIX)grpc++_reflection$(SHARED_VERSION_CPP).$(SHARED_EXT_CPP) $(prefix)/lib/libgrpc++_reflection.so.4
+	$(Q) ln -sf $(SHARED_PREFIX)grpc++_reflection$(SHARED_VERSION_CPP).$(SHARED_EXT_CPP) $(prefix)/lib/libgrpc++_reflection.so.5
 	$(Q) ln -sf $(SHARED_PREFIX)grpc++_reflection$(SHARED_VERSION_CPP).$(SHARED_EXT_CPP) $(prefix)/lib/libgrpc++_reflection.so
 endif
 	$(E) "[INSTALL] Installing $(SHARED_PREFIX)grpc++_unsecure$(SHARED_VERSION_CPP).$(SHARED_EXT_CPP)"
@@ -2708,7 +2708,7 @@ endif
 ifeq ($(SYSTEM),MINGW32)
 	$(Q) $(INSTALL) $(LIBDIR)/$(CONFIG)/libgrpc++_unsecure$(SHARED_VERSION_CPP)-dll.a $(prefix)/lib/libgrpc++_unsecure.a
 else ifneq ($(SYSTEM),Darwin)
-	$(Q) ln -sf $(SHARED_PREFIX)grpc++_unsecure$(SHARED_VERSION_CPP).$(SHARED_EXT_CPP) $(prefix)/lib/libgrpc++_unsecure.so.4
+	$(Q) ln -sf $(SHARED_PREFIX)grpc++_unsecure$(SHARED_VERSION_CPP).$(SHARED_EXT_CPP) $(prefix)/lib/libgrpc++_unsecure.so.5
 	$(Q) ln -sf $(SHARED_PREFIX)grpc++_unsecure$(SHARED_VERSION_CPP).$(SHARED_EXT_CPP) $(prefix)/lib/libgrpc++_unsecure.so
 endif
 ifneq ($(SYSTEM),MINGW32)
@@ -2725,7 +2725,7 @@ install-shared_csharp: shared_csharp strip-shared_csharp
 ifeq ($(SYSTEM),MINGW32)
 	$(Q) $(INSTALL) $(LIBDIR)/$(CONFIG)/libgrpc_csharp_ext$(SHARED_VERSION_CSHARP)-dll.a $(prefix)/lib/libgrpc_csharp_ext.a
 else ifneq ($(SYSTEM),Darwin)
-	$(Q) ln -sf $(SHARED_PREFIX)grpc_csharp_ext$(SHARED_VERSION_CSHARP).$(SHARED_EXT_CSHARP) $(prefix)/lib/libgrpc_csharp_ext.so.4
+	$(Q) ln -sf $(SHARED_PREFIX)grpc_csharp_ext$(SHARED_VERSION_CSHARP).$(SHARED_EXT_CSHARP) $(prefix)/lib/libgrpc_csharp_ext.so.5
 	$(Q) ln -sf $(SHARED_PREFIX)grpc_csharp_ext$(SHARED_VERSION_CSHARP).$(SHARED_EXT_CSHARP) $(prefix)/lib/libgrpc_csharp_ext.so
 endif
 ifneq ($(SYSTEM),MINGW32)
@@ -2892,8 +2892,8 @@ $(LIBDIR)/$(CONFIG)/libgpr$(SHARED_VERSION_CORE).$(SHARED_EXT_CORE): $(LIBGPR_OB
 ifeq ($(SYSTEM),Darwin)
 	$(Q) $(LD) $(LDFLAGS) -L$(LIBDIR)/$(CONFIG) -install_name $(SHARED_PREFIX)gpr$(SHARED_VERSION_CORE).$(SHARED_EXT_CORE) -dynamiclib -o $(LIBDIR)/$(CONFIG)/libgpr$(SHARED_VERSION_CORE).$(SHARED_EXT_CORE) $(LIBGPR_OBJS) $(ZLIB_MERGE_LIBS) $(CARES_MERGE_LIBS) $(LDLIBS)
 else
-	$(Q) $(LD) $(LDFLAGS) -L$(LIBDIR)/$(CONFIG) -shared -Wl,-soname,libgpr.so.4 -o $(LIBDIR)/$(CONFIG)/libgpr$(SHARED_VERSION_CORE).$(SHARED_EXT_CORE) $(LIBGPR_OBJS) $(ZLIB_MERGE_LIBS) $(CARES_MERGE_LIBS) $(LDLIBS)
-	$(Q) ln -sf $(SHARED_PREFIX)gpr$(SHARED_VERSION_CORE).$(SHARED_EXT_CORE) $(LIBDIR)/$(CONFIG)/libgpr$(SHARED_VERSION_CORE).so.4
+	$(Q) $(LD) $(LDFLAGS) -L$(LIBDIR)/$(CONFIG) -shared -Wl,-soname,libgpr.so.5 -o $(LIBDIR)/$(CONFIG)/libgpr$(SHARED_VERSION_CORE).$(SHARED_EXT_CORE) $(LIBGPR_OBJS) $(ZLIB_MERGE_LIBS) $(CARES_MERGE_LIBS) $(LDLIBS)
+	$(Q) ln -sf $(SHARED_PREFIX)gpr$(SHARED_VERSION_CORE).$(SHARED_EXT_CORE) $(LIBDIR)/$(CONFIG)/libgpr$(SHARED_VERSION_CORE).so.5
 	$(Q) ln -sf $(SHARED_PREFIX)gpr$(SHARED_VERSION_CORE).$(SHARED_EXT_CORE) $(LIBDIR)/$(CONFIG)/libgpr$(SHARED_VERSION_CORE).so
 endif
 endif
@@ -3261,8 +3261,8 @@ $(LIBDIR)/$(CONFIG)/libgrpc$(SHARED_VERSION_CORE).$(SHARED_EXT_CORE): $(LIBGRPC_
 ifeq ($(SYSTEM),Darwin)
 	$(Q) $(LD) $(LDFLAGS) -L$(LIBDIR)/$(CONFIG) -install_name $(SHARED_PREFIX)grpc$(SHARED_VERSION_CORE).$(SHARED_EXT_CORE) -dynamiclib -o $(LIBDIR)/$(CONFIG)/libgrpc$(SHARED_VERSION_CORE).$(SHARED_EXT_CORE) $(LIBGRPC_OBJS) $(LIBDIR)/$(CONFIG)/libgpr.a $(OPENSSL_MERGE_LIBS) $(LDLIBS_SECURE) $(ZLIB_MERGE_LIBS) $(CARES_MERGE_LIBS) $(LDLIBS)
 else
-	$(Q) $(LD) $(LDFLAGS) -L$(LIBDIR)/$(CONFIG) -shared -Wl,-soname,libgrpc.so.4 -o $(LIBDIR)/$(CONFIG)/libgrpc$(SHARED_VERSION_CORE).$(SHARED_EXT_CORE) $(LIBGRPC_OBJS) $(LIBDIR)/$(CONFIG)/libgpr.a $(OPENSSL_MERGE_LIBS) $(LDLIBS_SECURE) $(ZLIB_MERGE_LIBS) $(CARES_MERGE_LIBS) $(LDLIBS)
-	$(Q) ln -sf $(SHARED_PREFIX)grpc$(SHARED_VERSION_CORE).$(SHARED_EXT_CORE) $(LIBDIR)/$(CONFIG)/libgrpc$(SHARED_VERSION_CORE).so.4
+	$(Q) $(LD) $(LDFLAGS) -L$(LIBDIR)/$(CONFIG) -shared -Wl,-soname,libgrpc.so.5 -o $(LIBDIR)/$(CONFIG)/libgrpc$(SHARED_VERSION_CORE).$(SHARED_EXT_CORE) $(LIBGRPC_OBJS) $(LIBDIR)/$(CONFIG)/libgpr.a $(OPENSSL_MERGE_LIBS) $(LDLIBS_SECURE) $(ZLIB_MERGE_LIBS) $(CARES_MERGE_LIBS) $(LDLIBS)
+	$(Q) ln -sf $(SHARED_PREFIX)grpc$(SHARED_VERSION_CORE).$(SHARED_EXT_CORE) $(LIBDIR)/$(CONFIG)/libgrpc$(SHARED_VERSION_CORE).so.5
 	$(Q) ln -sf $(SHARED_PREFIX)grpc$(SHARED_VERSION_CORE).$(SHARED_EXT_CORE) $(LIBDIR)/$(CONFIG)/libgrpc$(SHARED_VERSION_CORE).so
 endif
 endif
@@ -3557,8 +3557,8 @@ $(LIBDIR)/$(CONFIG)/libgrpc_cronet$(SHARED_VERSION_CORE).$(SHARED_EXT_CORE): $(L
 ifeq ($(SYSTEM),Darwin)
 	$(Q) $(LD) $(LDFLAGS) -L$(LIBDIR)/$(CONFIG) -install_name $(SHARED_PREFIX)grpc_cronet$(SHARED_VERSION_CORE).$(SHARED_EXT_CORE) -dynamiclib -o $(LIBDIR)/$(CONFIG)/libgrpc_cronet$(SHARED_VERSION_CORE).$(SHARED_EXT_CORE) $(LIBGRPC_CRONET_OBJS) $(LIBDIR)/$(CONFIG)/libgpr.a $(OPENSSL_MERGE_LIBS) $(LDLIBS_SECURE) $(ZLIB_MERGE_LIBS) $(CARES_MERGE_LIBS) $(LDLIBS)
 else
-	$(Q) $(LD) $(LDFLAGS) -L$(LIBDIR)/$(CONFIG) -shared -Wl,-soname,libgrpc_cronet.so.4 -o $(LIBDIR)/$(CONFIG)/libgrpc_cronet$(SHARED_VERSION_CORE).$(SHARED_EXT_CORE) $(LIBGRPC_CRONET_OBJS) $(LIBDIR)/$(CONFIG)/libgpr.a $(OPENSSL_MERGE_LIBS) $(LDLIBS_SECURE) $(ZLIB_MERGE_LIBS) $(CARES_MERGE_LIBS) $(LDLIBS)
-	$(Q) ln -sf $(SHARED_PREFIX)grpc_cronet$(SHARED_VERSION_CORE).$(SHARED_EXT_CORE) $(LIBDIR)/$(CONFIG)/libgrpc_cronet$(SHARED_VERSION_CORE).so.4
+	$(Q) $(LD) $(LDFLAGS) -L$(LIBDIR)/$(CONFIG) -shared -Wl,-soname,libgrpc_cronet.so.5 -o $(LIBDIR)/$(CONFIG)/libgrpc_cronet$(SHARED_VERSION_CORE).$(SHARED_EXT_CORE) $(LIBGRPC_CRONET_OBJS) $(LIBDIR)/$(CONFIG)/libgpr.a $(OPENSSL_MERGE_LIBS) $(LDLIBS_SECURE) $(ZLIB_MERGE_LIBS) $(CARES_MERGE_LIBS) $(LDLIBS)
+	$(Q) ln -sf $(SHARED_PREFIX)grpc_cronet$(SHARED_VERSION_CORE).$(SHARED_EXT_CORE) $(LIBDIR)/$(CONFIG)/libgrpc_cronet$(SHARED_VERSION_CORE).so.5
 	$(Q) ln -sf $(SHARED_PREFIX)grpc_cronet$(SHARED_VERSION_CORE).$(SHARED_EXT_CORE) $(LIBDIR)/$(CONFIG)/libgrpc_cronet$(SHARED_VERSION_CORE).so
 endif
 endif
@@ -4355,8 +4355,8 @@ $(LIBDIR)/$(CONFIG)/libgrpc_unsecure$(SHARED_VERSION_CORE).$(SHARED_EXT_CORE): $
 ifeq ($(SYSTEM),Darwin)
 	$(Q) $(LD) $(LDFLAGS) -L$(LIBDIR)/$(CONFIG) -install_name $(SHARED_PREFIX)grpc_unsecure$(SHARED_VERSION_CORE).$(SHARED_EXT_CORE) -dynamiclib -o $(LIBDIR)/$(CONFIG)/libgrpc_unsecure$(SHARED_VERSION_CORE).$(SHARED_EXT_CORE) $(LIBGRPC_UNSECURE_OBJS) $(LIBDIR)/$(CONFIG)/libgpr.a $(ZLIB_MERGE_LIBS) $(CARES_MERGE_LIBS) $(LDLIBS)
 else
-	$(Q) $(LD) $(LDFLAGS) -L$(LIBDIR)/$(CONFIG) -shared -Wl,-soname,libgrpc_unsecure.so.4 -o $(LIBDIR)/$(CONFIG)/libgrpc_unsecure$(SHARED_VERSION_CORE).$(SHARED_EXT_CORE) $(LIBGRPC_UNSECURE_OBJS) $(LIBDIR)/$(CONFIG)/libgpr.a $(ZLIB_MERGE_LIBS) $(CARES_MERGE_LIBS) $(LDLIBS)
-	$(Q) ln -sf $(SHARED_PREFIX)grpc_unsecure$(SHARED_VERSION_CORE).$(SHARED_EXT_CORE) $(LIBDIR)/$(CONFIG)/libgrpc_unsecure$(SHARED_VERSION_CORE).so.4
+	$(Q) $(LD) $(LDFLAGS) -L$(LIBDIR)/$(CONFIG) -shared -Wl,-soname,libgrpc_unsecure.so.5 -o $(LIBDIR)/$(CONFIG)/libgrpc_unsecure$(SHARED_VERSION_CORE).$(SHARED_EXT_CORE) $(LIBGRPC_UNSECURE_OBJS) $(LIBDIR)/$(CONFIG)/libgpr.a $(ZLIB_MERGE_LIBS) $(CARES_MERGE_LIBS) $(LDLIBS)
+	$(Q) ln -sf $(SHARED_PREFIX)grpc_unsecure$(SHARED_VERSION_CORE).$(SHARED_EXT_CORE) $(LIBDIR)/$(CONFIG)/libgrpc_unsecure$(SHARED_VERSION_CORE).so.5
 	$(Q) ln -sf $(SHARED_PREFIX)grpc_unsecure$(SHARED_VERSION_CORE).$(SHARED_EXT_CORE) $(LIBDIR)/$(CONFIG)/libgrpc_unsecure$(SHARED_VERSION_CORE).so
 endif
 endif
diff --git a/build.yaml b/build.yaml
index 5dc59e0ff9..502a074744 100644
--- a/build.yaml
+++ b/build.yaml
@@ -12,7 +12,7 @@ settings:
   '#08': Use "-preN" suffixes to identify pre-release versions
   '#09': Per-language overrides are possible with (eg) ruby_version tag here
   '#10': See the expand_version.py for all the quirks here
-  core_version: 4.0.0-dev
+  core_version: 5.0.0-dev
   g_stands_for: gambit
   version: 1.7.0-dev
 filegroups:
diff --git a/build_config.rb b/build_config.rb
index 7159c6e509..3dc31d4ce3 100644
--- a/build_config.rb
+++ b/build_config.rb
@@ -13,5 +13,5 @@
 # limitations under the License.
 
 module GrpcBuildConfig
-  CORE_WINDOWS_DLL = '/tmp/libs/opt/grpc-4.dll'
+  CORE_WINDOWS_DLL = '/tmp/libs/opt/grpc-5.dll'
 end
diff --git a/grpc.def b/grpc.def
index 37cc7e20f0..a7a11601ed 100644
--- a/grpc.def
+++ b/grpc.def
@@ -65,6 +65,7 @@ EXPORTS
     grpc_completion_queue_shutdown
     grpc_completion_queue_destroy
     grpc_alarm_create
+    grpc_alarm_set
     grpc_alarm_cancel
     grpc_alarm_destroy
     grpc_channel_check_connectivity_state
diff --git a/include/grpc++/alarm.h b/include/grpc++/alarm.h
index ed8dacbc94..2d88d868e5 100644
--- a/include/grpc++/alarm.h
+++ b/include/grpc++/alarm.h
@@ -37,20 +37,33 @@ class CompletionQueue;
 /// A thin wrapper around \a grpc_alarm (see / \a / src/core/surface/alarm.h).
 class Alarm : private GrpcLibraryCodegen {
  public:
-  /// Create a completion queue alarm instance associated to \a cq.
-  ///
-  /// Once the alarm expires (at \a deadline) or it's cancelled (see \a Cancel),
-  /// an event with tag \a tag will be added to \a cq. If the alarm expired, the
-  /// event's success bit will be true, false otherwise (ie, upon cancellation).
+  /// Create an unset completion queue alarm
+  Alarm() : tag_(nullptr), alarm_(grpc_alarm_create(nullptr)) {}
+
+  /// DEPRECATED: Create and set a completion queue alarm instance associated to
+  /// \a cq.
+  /// This form is deprecated because it is inherently racy.
   /// \internal We rely on the presence of \a cq for grpc initialization. If \a
   /// cq were ever to be removed, a reference to a static
   /// internal::GrpcLibraryInitializer instance would need to be introduced
   /// here. \endinternal.
   template <typename T>
   Alarm(CompletionQueue* cq, const T& deadline, void* tag)
-      : tag_(tag),
-        alarm_(grpc_alarm_create(cq->cq(), TimePoint<T>(deadline).raw_time(),
-                                 static_cast<void*>(&tag_))) {}
+      : tag_(tag), alarm_(grpc_alarm_create(nullptr)) {
+    grpc_alarm_set(alarm_, cq->cq(), TimePoint<T>(deadline).raw_time(),
+                   static_cast<void*>(&tag_), nullptr);
+  }
+
+  /// Trigger an alarm instance on completion queue \a cq at the specified time.
+  /// Once the alarm expires (at \a deadline) or it's cancelled (see \a Cancel),
+  /// an event with tag \a tag will be added to \a cq. If the alarm expired, the
+  /// event's success bit will be true, false otherwise (ie, upon cancellation).
+  template <typename T>
+  void Set(CompletionQueue* cq, const T& deadline, void* tag) {
+    tag_.Set(tag);
+    grpc_alarm_set(alarm_, cq->cq(), TimePoint<T>(deadline).raw_time(),
+                   static_cast<void*>(&tag_), nullptr);
+  }
 
   /// Alarms aren't copyable.
   Alarm(const Alarm&) = delete;
@@ -69,17 +82,20 @@ class Alarm : private GrpcLibraryCodegen {
 
   /// Destroy the given completion queue alarm, cancelling it in the process.
   ~Alarm() {
-    if (alarm_ != nullptr) grpc_alarm_destroy(alarm_);
+    if (alarm_ != nullptr) grpc_alarm_destroy(alarm_, nullptr);
   }
 
   /// Cancel a completion queue alarm. Calling this function over an alarm that
   /// has already fired has no effect.
-  void Cancel() { grpc_alarm_cancel(alarm_); }
+  void Cancel() {
+    if (alarm_ != nullptr) grpc_alarm_cancel(alarm_, nullptr);
+  }
 
  private:
   class AlarmEntry : public CompletionQueueTag {
    public:
     AlarmEntry(void* tag) : tag_(tag) {}
+    void Set(void* tag) { tag_ = tag; }
     bool FinalizeResult(void** tag, bool* status) override {
       *tag = tag_;
       return true;
diff --git a/include/grpc/grpc.h b/include/grpc/grpc.h
index b562167b5f..fab7d438aa 100644
--- a/include/grpc/grpc.h
+++ b/include/grpc/grpc.h
@@ -143,21 +143,24 @@ GRPCAPI void grpc_completion_queue_shutdown(grpc_completion_queue *cq);
     drained and no threads are executing grpc_completion_queue_next */
 GRPCAPI void grpc_completion_queue_destroy(grpc_completion_queue *cq);
 
-/** Create a completion queue alarm instance associated to \a cq.
+/** Create a completion queue alarm instance */
+GRPCAPI grpc_alarm *grpc_alarm_create(void *reserved);
+
+/** Set a completion queue alarm instance associated to \a cq.
  *
  * Once the alarm expires (at \a deadline) or it's cancelled (see \a
  * grpc_alarm_cancel), an event with tag \a tag will be added to \a cq. If the
  * alarm expired, the event's success bit will be true, false otherwise (ie,
  * upon cancellation). */
-GRPCAPI grpc_alarm *grpc_alarm_create(grpc_completion_queue *cq,
-                                      gpr_timespec deadline, void *tag);
+GRPCAPI void grpc_alarm_set(grpc_alarm *alarm, grpc_completion_queue *cq,
+                            gpr_timespec deadline, void *tag, void *reserved);
 
 /** Cancel a completion queue alarm. Calling this function over an alarm that
  * has already fired has no effect. */
-GRPCAPI void grpc_alarm_cancel(grpc_alarm *alarm);
+GRPCAPI void grpc_alarm_cancel(grpc_alarm *alarm, void *reserved);
 
 /** Destroy the given completion queue alarm, cancelling it in the process. */
-GRPCAPI void grpc_alarm_destroy(grpc_alarm *alarm);
+GRPCAPI void grpc_alarm_destroy(grpc_alarm *alarm, void *reserved);
 
 /** Check the connectivity state of a channel. */
 GRPCAPI grpc_connectivity_state grpc_channel_check_connectivity_state(
diff --git a/src/core/lib/iomgr/timer.h b/src/core/lib/iomgr/timer.h
index b92b8fb8b8..ac392f87fe 100644
--- a/src/core/lib/iomgr/timer.h
+++ b/src/core/lib/iomgr/timer.h
@@ -44,6 +44,10 @@ void grpc_timer_init(grpc_exec_ctx *exec_ctx, grpc_timer *timer,
                      gpr_timespec deadline, grpc_closure *closure,
                      gpr_timespec now);
 
+/* Initialize *timer without setting it. This can later be passed through
+   the regular init or cancel */
+void grpc_timer_init_unset(grpc_timer *timer);
+
 /* Note that there is no timer destroy function. This is because the
    timer is a one-time occurrence with a guarantee that the callback will
    be called exactly once, either at expiration or cancellation. Thus, all
diff --git a/src/core/lib/iomgr/timer_generic.c b/src/core/lib/iomgr/timer_generic.c
index 12efce241f..c08bb525b7 100644
--- a/src/core/lib/iomgr/timer_generic.c
+++ b/src/core/lib/iomgr/timer_generic.c
@@ -234,6 +234,8 @@ static void note_deadline_change(timer_shard *shard) {
   }
 }
 
+void grpc_timer_init_unset(grpc_timer *timer) { timer->pending = false; }
+
 void grpc_timer_init(grpc_exec_ctx *exec_ctx, grpc_timer *timer,
                      gpr_timespec deadline, grpc_closure *closure,
                      gpr_timespec now) {
diff --git a/src/core/lib/iomgr/timer_uv.c b/src/core/lib/iomgr/timer_uv.c
index 70f49bcbe8..adced41f53 100644
--- a/src/core/lib/iomgr/timer_uv.c
+++ b/src/core/lib/iomgr/timer_uv.c
@@ -77,6 +77,8 @@ void grpc_timer_init(grpc_exec_ctx *exec_ctx, grpc_timer *timer,
   uv_unref((uv_handle_t *)uv_timer);
 }
 
+void grpc_timer_init_unset(grpc_timer *timer) { timer->pending = 0; }
+
 void grpc_timer_cancel(grpc_exec_ctx *exec_ctx, grpc_timer *timer) {
   GRPC_UV_ASSERT_SAME_THREAD();
   if (timer->pending) {
diff --git a/src/core/lib/surface/alarm.c b/src/core/lib/surface/alarm.c
index 7d60b1de17..5dbfaa2d43 100644
--- a/src/core/lib/surface/alarm.c
+++ b/src/core/lib/surface/alarm.c
@@ -44,7 +44,9 @@ static void alarm_ref(grpc_alarm *alarm) { gpr_ref(&alarm->refs); }
 static void alarm_unref(grpc_alarm *alarm) {
   if (gpr_unref(&alarm->refs)) {
     grpc_exec_ctx exec_ctx = GRPC_EXEC_CTX_INIT;
-    GRPC_CQ_INTERNAL_UNREF(&exec_ctx, alarm->cq, "alarm");
+    if (alarm->cq != NULL) {
+      GRPC_CQ_INTERNAL_UNREF(&exec_ctx, alarm->cq, "alarm");
+    }
     grpc_exec_ctx_finish(&exec_ctx);
     gpr_free(alarm);
   }
@@ -93,12 +95,8 @@ static void alarm_cb(grpc_exec_ctx *exec_ctx, void *arg, grpc_error *error) {
                  (void *)alarm, &alarm->completion);
 }
 
-grpc_alarm *grpc_alarm_create(grpc_completion_queue *cq, gpr_timespec deadline,
-                              void *tag) {
+grpc_alarm *grpc_alarm_create(void *reserved) {
   grpc_alarm *alarm = gpr_malloc(sizeof(grpc_alarm));
-  grpc_exec_ctx exec_ctx = GRPC_EXEC_CTX_INIT;
-
-  gpr_ref_init(&alarm->refs, 1);
 
 #ifndef NDEBUG
   if (GRPC_TRACER_ON(grpc_trace_alarm_refcount)) {
@@ -106,27 +104,36 @@ grpc_alarm *grpc_alarm_create(grpc_completion_queue *cq, gpr_timespec deadline,
   }
 #endif
 
+  gpr_ref_init(&alarm->refs, 1);
+  grpc_timer_init_unset(&alarm->alarm);
+  alarm->cq = NULL;
+  GRPC_CLOSURE_INIT(&alarm->on_alarm, alarm_cb, alarm,
+                    grpc_schedule_on_exec_ctx);
+  return alarm;
+}
+
+void grpc_alarm_set(grpc_alarm *alarm, grpc_completion_queue *cq,
+                    gpr_timespec deadline, void *tag, void *reserved) {
+  grpc_exec_ctx exec_ctx = GRPC_EXEC_CTX_INIT;
+
   GRPC_CQ_INTERNAL_REF(cq, "alarm");
   alarm->cq = cq;
   alarm->tag = tag;
 
   GPR_ASSERT(grpc_cq_begin_op(cq, tag));
-  GRPC_CLOSURE_INIT(&alarm->on_alarm, alarm_cb, alarm,
-                    grpc_schedule_on_exec_ctx);
   grpc_timer_init(&exec_ctx, &alarm->alarm,
                   gpr_convert_clock_type(deadline, GPR_CLOCK_MONOTONIC),
                   &alarm->on_alarm, gpr_now(GPR_CLOCK_MONOTONIC));
   grpc_exec_ctx_finish(&exec_ctx);
-  return alarm;
 }
 
-void grpc_alarm_cancel(grpc_alarm *alarm) {
+void grpc_alarm_cancel(grpc_alarm *alarm, void *reserved) {
   grpc_exec_ctx exec_ctx = GRPC_EXEC_CTX_INIT;
   grpc_timer_cancel(&exec_ctx, &alarm->alarm);
   grpc_exec_ctx_finish(&exec_ctx);
 }
 
-void grpc_alarm_destroy(grpc_alarm *alarm) {
-  grpc_alarm_cancel(alarm);
+void grpc_alarm_destroy(grpc_alarm *alarm, void *reserved) {
+  grpc_alarm_cancel(alarm, reserved);
   GRPC_ALARM_UNREF(alarm, "alarm_destroy");
 }
diff --git a/src/core/lib/surface/version.c b/src/core/lib/surface/version.c
index 96c16105e7..fd6ea4daa9 100644
--- a/src/core/lib/surface/version.c
+++ b/src/core/lib/surface/version.c
@@ -21,6 +21,6 @@
 
 #include <grpc/grpc.h>
 
-const char *grpc_version_string(void) { return "4.0.0-dev"; }
+const char *grpc_version_string(void) { return "5.0.0-dev"; }
 
 const char *grpc_g_stands_for(void) { return "gambit"; }
diff --git a/src/ruby/ext/grpc/rb_grpc_imports.generated.c b/src/ruby/ext/grpc/rb_grpc_imports.generated.c
index 0402ce34fb..57b543967e 100644
--- a/src/ruby/ext/grpc/rb_grpc_imports.generated.c
+++ b/src/ruby/ext/grpc/rb_grpc_imports.generated.c
@@ -88,6 +88,7 @@ grpc_completion_queue_pluck_type grpc_completion_queue_pluck_import;
 grpc_completion_queue_shutdown_type grpc_completion_queue_shutdown_import;
 grpc_completion_queue_destroy_type grpc_completion_queue_destroy_import;
 grpc_alarm_create_type grpc_alarm_create_import;
+grpc_alarm_set_type grpc_alarm_set_import;
 grpc_alarm_cancel_type grpc_alarm_cancel_import;
 grpc_alarm_destroy_type grpc_alarm_destroy_import;
 grpc_channel_check_connectivity_state_type grpc_channel_check_connectivity_state_import;
@@ -395,6 +396,7 @@ void grpc_rb_load_imports(HMODULE library) {
   grpc_completion_queue_shutdown_import = (grpc_completion_queue_shutdown_type) GetProcAddress(library, "grpc_completion_queue_shutdown");
   grpc_completion_queue_destroy_import = (grpc_completion_queue_destroy_type) GetProcAddress(library, "grpc_completion_queue_destroy");
   grpc_alarm_create_import = (grpc_alarm_create_type) GetProcAddress(library, "grpc_alarm_create");
+  grpc_alarm_set_import = (grpc_alarm_set_type) GetProcAddress(library, "grpc_alarm_set");
   grpc_alarm_cancel_import = (grpc_alarm_cancel_type) GetProcAddress(library, "grpc_alarm_cancel");
   grpc_alarm_destroy_import = (grpc_alarm_destroy_type) GetProcAddress(library, "grpc_alarm_destroy");
   grpc_channel_check_connectivity_state_import = (grpc_channel_check_connectivity_state_type) GetProcAddress(library, "grpc_channel_check_connectivity_state");
diff --git a/src/ruby/ext/grpc/rb_grpc_imports.generated.h b/src/ruby/ext/grpc/rb_grpc_imports.generated.h
index e3704e592b..c5c848ae44 100644
--- a/src/ruby/ext/grpc/rb_grpc_imports.generated.h
+++ b/src/ruby/ext/grpc/rb_grpc_imports.generated.h
@@ -242,13 +242,16 @@ extern grpc_completion_queue_shutdown_type grpc_completion_queue_shutdown_import
 typedef void(*grpc_completion_queue_destroy_type)(grpc_completion_queue *cq);
 extern grpc_completion_queue_destroy_type grpc_completion_queue_destroy_import;
 #define grpc_completion_queue_destroy grpc_completion_queue_destroy_import
-typedef grpc_alarm *(*grpc_alarm_create_type)(grpc_completion_queue *cq, gpr_timespec deadline, void *tag);
+typedef grpc_alarm *(*grpc_alarm_create_type)(void *reserved);
 extern grpc_alarm_create_type grpc_alarm_create_import;
 #define grpc_alarm_create grpc_alarm_create_import
-typedef void(*grpc_alarm_cancel_type)(grpc_alarm *alarm);
+typedef void(*grpc_alarm_set_type)(grpc_alarm *alarm, grpc_completion_queue *cq, gpr_timespec deadline, void *tag, void *reserved);
+extern grpc_alarm_set_type grpc_alarm_set_import;
+#define grpc_alarm_set grpc_alarm_set_import
+typedef void(*grpc_alarm_cancel_type)(grpc_alarm *alarm, void *reserved);
 extern grpc_alarm_cancel_type grpc_alarm_cancel_import;
 #define grpc_alarm_cancel grpc_alarm_cancel_import
-typedef void(*grpc_alarm_destroy_type)(grpc_alarm *alarm);
+typedef void(*grpc_alarm_destroy_type)(grpc_alarm *alarm, void *reserved);
 extern grpc_alarm_destroy_type grpc_alarm_destroy_import;
 #define grpc_alarm_destroy grpc_alarm_destroy_import
 typedef grpc_connectivity_state(*grpc_channel_check_connectivity_state_type)(grpc_channel *channel, int try_to_connect);
diff --git a/test/core/surface/alarm_test.c b/test/core/surface/alarm_test.c
index 6971d92074..4fd7cb93c6 100644
--- a/test/core/surface/alarm_test.c
+++ b/test/core/surface/alarm_test.c
@@ -48,45 +48,50 @@ static void test_alarm(void) {
     /* regular expiry */
     grpc_event ev;
     void *tag = create_test_tag();
-    grpc_alarm *alarm =
-        grpc_alarm_create(cc, grpc_timeout_seconds_to_deadline(1), tag);
+    grpc_alarm *alarm = grpc_alarm_create(NULL);
+    grpc_alarm_set(alarm, cc, grpc_timeout_seconds_to_deadline(1), tag, NULL);
 
     ev = grpc_completion_queue_next(cc, grpc_timeout_seconds_to_deadline(2),
                                     NULL);
     GPR_ASSERT(ev.type == GRPC_OP_COMPLETE);
     GPR_ASSERT(ev.tag == tag);
     GPR_ASSERT(ev.success);
-    grpc_alarm_destroy(alarm);
+    grpc_alarm_destroy(alarm, NULL);
   }
   {
     /* cancellation */
     grpc_event ev;
     void *tag = create_test_tag();
-    grpc_alarm *alarm =
-        grpc_alarm_create(cc, grpc_timeout_seconds_to_deadline(2), tag);
+    grpc_alarm *alarm = grpc_alarm_create(NULL);
+    grpc_alarm_set(alarm, cc, grpc_timeout_seconds_to_deadline(2), tag, NULL);
 
-    grpc_alarm_cancel(alarm);
+    grpc_alarm_cancel(alarm, NULL);
     ev = grpc_completion_queue_next(cc, grpc_timeout_seconds_to_deadline(1),
                                     NULL);
     GPR_ASSERT(ev.type == GRPC_OP_COMPLETE);
     GPR_ASSERT(ev.tag == tag);
     GPR_ASSERT(ev.success == 0);
-    grpc_alarm_destroy(alarm);
+    grpc_alarm_destroy(alarm, NULL);
   }
   {
     /* alarm_destroy before cq_next */
     grpc_event ev;
     void *tag = create_test_tag();
-    grpc_alarm *alarm =
-        grpc_alarm_create(cc, grpc_timeout_seconds_to_deadline(2), tag);
+    grpc_alarm *alarm = grpc_alarm_create(NULL);
+    grpc_alarm_set(alarm, cc, grpc_timeout_seconds_to_deadline(2), tag, NULL);
 
-    grpc_alarm_destroy(alarm);
+    grpc_alarm_destroy(alarm, NULL);
     ev = grpc_completion_queue_next(cc, grpc_timeout_seconds_to_deadline(1),
                                     NULL);
     GPR_ASSERT(ev.type == GRPC_OP_COMPLETE);
     GPR_ASSERT(ev.tag == tag);
     GPR_ASSERT(ev.success == 0);
   }
+  {
+    /* alarm_destroy before set */
+    grpc_alarm *alarm = grpc_alarm_create(NULL);
+    grpc_alarm_destroy(alarm, NULL);
+  }
 
   shutdown_and_destroy(cc);
 }
diff --git a/test/cpp/common/alarm_cpp_test.cc b/test/cpp/common/alarm_cpp_test.cc
index ce4168843c..212972d25d 100644
--- a/test/cpp/common/alarm_cpp_test.cc
+++ b/test/cpp/common/alarm_cpp_test.cc
@@ -18,6 +18,8 @@
 
 #include <grpc++/alarm.h>
 #include <grpc++/completion_queue.h>
+#include <thread>
+
 #include <gtest/gtest.h>
 
 #include "test/core/util/test_config.h"
@@ -28,6 +30,46 @@ namespace {
 TEST(AlarmTest, RegularExpiry) {
   CompletionQueue cq;
   void* junk = reinterpret_cast<void*>(1618033);
+  Alarm alarm;
+  alarm.Set(&cq, grpc_timeout_seconds_to_deadline(1), junk);
+
+  void* output_tag;
+  bool ok;
+  const CompletionQueue::NextStatus status = cq.AsyncNext(
+      (void**)&output_tag, &ok, grpc_timeout_seconds_to_deadline(2));
+
+  EXPECT_EQ(status, CompletionQueue::GOT_EVENT);
+  EXPECT_TRUE(ok);
+  EXPECT_EQ(junk, output_tag);
+}
+
+TEST(AlarmTest, MultithreadedRegularExpiry) {
+  CompletionQueue cq;
+  void* junk = reinterpret_cast<void*>(1618033);
+  void* output_tag;
+  bool ok;
+  CompletionQueue::NextStatus status;
+  Alarm alarm;
+
+  std::thread t1([&alarm, &cq, &junk] {
+    alarm.Set(&cq, grpc_timeout_seconds_to_deadline(1), junk);
+  });
+
+  std::thread t2([&cq, &ok, &output_tag, &status] {
+    status = cq.AsyncNext((void**)&output_tag, &ok,
+                          grpc_timeout_seconds_to_deadline(2));
+  });
+
+  t1.join();
+  t2.join();
+  EXPECT_EQ(status, CompletionQueue::GOT_EVENT);
+  EXPECT_TRUE(ok);
+  EXPECT_EQ(junk, output_tag);
+}
+
+TEST(AlarmTest, DeprecatedRegularExpiry) {
+  CompletionQueue cq;
+  void* junk = reinterpret_cast<void*>(1618033);
   Alarm alarm(&cq, grpc_timeout_seconds_to_deadline(1), junk);
 
   void* output_tag;
@@ -43,7 +85,8 @@ TEST(AlarmTest, RegularExpiry) {
 TEST(AlarmTest, MoveConstructor) {
   CompletionQueue cq;
   void* junk = reinterpret_cast<void*>(1618033);
-  Alarm first(&cq, grpc_timeout_seconds_to_deadline(1), junk);
+  Alarm first;
+  first.Set(&cq, grpc_timeout_seconds_to_deadline(1), junk);
   Alarm second(std::move(first));
   void* output_tag;
   bool ok;
@@ -57,7 +100,8 @@ TEST(AlarmTest, MoveConstructor) {
 TEST(AlarmTest, MoveAssignment) {
   CompletionQueue cq;
   void* junk = reinterpret_cast<void*>(1618033);
-  Alarm first(&cq, grpc_timeout_seconds_to_deadline(1), junk);
+  Alarm first;
+  first.Set(&cq, grpc_timeout_seconds_to_deadline(1), junk);
   Alarm second(std::move(first));
   first = std::move(second);
 
@@ -76,7 +120,8 @@ TEST(AlarmTest, RegularExpiryChrono) {
   void* junk = reinterpret_cast<void*>(1618033);
   std::chrono::system_clock::time_point one_sec_deadline =
       std::chrono::system_clock::now() + std::chrono::seconds(1);
-  Alarm alarm(&cq, one_sec_deadline, junk);
+  Alarm alarm;
+  alarm.Set(&cq, one_sec_deadline, junk);
 
   void* output_tag;
   bool ok;
@@ -91,7 +136,8 @@ TEST(AlarmTest, RegularExpiryChrono) {
 TEST(AlarmTest, ZeroExpiry) {
   CompletionQueue cq;
   void* junk = reinterpret_cast<void*>(1618033);
-  Alarm alarm(&cq, grpc_timeout_seconds_to_deadline(0), junk);
+  Alarm alarm;
+  alarm.Set(&cq, grpc_timeout_seconds_to_deadline(0), junk);
 
   void* output_tag;
   bool ok;
@@ -106,7 +152,8 @@ TEST(AlarmTest, ZeroExpiry) {
 TEST(AlarmTest, NegativeExpiry) {
   CompletionQueue cq;
   void* junk = reinterpret_cast<void*>(1618033);
-  Alarm alarm(&cq, grpc_timeout_seconds_to_deadline(-1), junk);
+  Alarm alarm;
+  alarm.Set(&cq, grpc_timeout_seconds_to_deadline(-1), junk);
 
   void* output_tag;
   bool ok;
@@ -121,7 +168,8 @@ TEST(AlarmTest, NegativeExpiry) {
 TEST(AlarmTest, Cancellation) {
   CompletionQueue cq;
   void* junk = reinterpret_cast<void*>(1618033);
-  Alarm alarm(&cq, grpc_timeout_seconds_to_deadline(2), junk);
+  Alarm alarm;
+  alarm.Set(&cq, grpc_timeout_seconds_to_deadline(2), junk);
   alarm.Cancel();
 
   void* output_tag;
diff --git a/test/cpp/qps/client_async.cc b/test/cpp/qps/client_async.cc
index 97e2aef914..912c871482 100644
--- a/test/cpp/qps/client_async.cc
+++ b/test/cpp/qps/client_async.cc
@@ -141,7 +141,8 @@ class ClientRpcContextUnaryImpl : public ClientRpcContext {
     if (!next_issue_) {  // ready to issue
       RunNextState(true, nullptr);
     } else {  // wait for the issue time
-      alarm_.reset(new Alarm(cq_, next_issue_(), ClientRpcContext::tag(this)));
+      alarm_.reset(new Alarm);
+      alarm_->Set(cq_, next_issue_(), ClientRpcContext::tag(this));
     }
   }
 };
@@ -360,8 +361,8 @@ class ClientRpcContextStreamingPingPongImpl : public ClientRpcContext {
           break;  // loop around, don't return
         case State::WAIT:
           next_state_ = State::READY_TO_WRITE;
-          alarm_.reset(
-              new Alarm(cq_, next_issue_(), ClientRpcContext::tag(this)));
+          alarm_.reset(new Alarm);
+          alarm_->Set(cq_, next_issue_(), ClientRpcContext::tag(this));
           return true;
         case State::READY_TO_WRITE:
           if (!ok) {
@@ -518,8 +519,8 @@ class ClientRpcContextStreamingFromClientImpl : public ClientRpcContext {
           }
           break;  // loop around, don't return
         case State::WAIT:
-          alarm_.reset(
-              new Alarm(cq_, next_issue_(), ClientRpcContext::tag(this)));
+          alarm_.reset(new Alarm);
+          alarm_->Set(cq_, next_issue_(), ClientRpcContext::tag(this));
           next_state_ = State::READY_TO_WRITE;
           return true;
         case State::READY_TO_WRITE:
@@ -760,8 +761,8 @@ class ClientRpcContextGenericStreamingImpl : public ClientRpcContext {
           break;  // loop around, don't return
         case State::WAIT:
           next_state_ = State::READY_TO_WRITE;
-          alarm_.reset(
-              new Alarm(cq_, next_issue_(), ClientRpcContext::tag(this)));
+          alarm_.reset(new Alarm);
+          alarm_->Set(cq_, next_issue_(), ClientRpcContext::tag(this));
           return true;
         case State::READY_TO_WRITE:
           if (!ok) {
diff --git a/tools/doxygen/Doxyfile.core b/tools/doxygen/Doxyfile.core
index e4cc1c7461..632735342b 100644
--- a/tools/doxygen/Doxyfile.core
+++ b/tools/doxygen/Doxyfile.core
@@ -40,7 +40,7 @@ PROJECT_NAME           = "GRPC Core"
 # could be handy for archiving the generated documentation or if some version
 # control system is used.
 
-PROJECT_NUMBER         = 4.0.0-dev
+PROJECT_NUMBER         = 5.0.0-dev
 
 # Using the PROJECT_BRIEF tag one can provide an optional one line description
 # for a project that appears at the top of each page and should give viewer a
diff --git a/tools/doxygen/Doxyfile.core.internal b/tools/doxygen/Doxyfile.core.internal
index c2daf900fb..631988f2a6 100644
--- a/tools/doxygen/Doxyfile.core.internal
+++ b/tools/doxygen/Doxyfile.core.internal
@@ -40,7 +40,7 @@ PROJECT_NAME           = "GRPC Core"
 # could be handy for archiving the generated documentation or if some version
 # control system is used.
 
-PROJECT_NUMBER         = 4.0.0-dev
+PROJECT_NUMBER         = 5.0.0-dev
 
 # Using the PROJECT_BRIEF tag one can provide an optional one line description
 # for a project that appears at the top of each page and should give viewer a